require('./main.css') 
const {toLowerCase,toUpperCase} = require('./b.js')
const a = 'Hello 严总,帅的惊动党中央'
console.log(toLowerCase(a))
console.log(toUpperCase(a))
let Div = document.createElement('div')
Div.textContent = "严总真帅"
document.body.appendChild(
    Div
)
module.export = a; // commonjs